Ch 24: The Milky Way Galaxy: Help and Review

About This Chapter

The Milky Way Galaxy chapter of this Intro to Astronomy Help and Review course is the simplest way to master the Milky Way. This chapter uses simple and fun videos that are about five minutes long, plus lesson quizzes and a chapter exam to ensure students learn the essentials of the Milky Way Galaxy.

Who's it for?

Anyone who needs help learning or mastering Intro to Astronomy material will benefit from taking this course. There is no faster or easier way to learn introductory astronomy. Among those who would benefit are:

  • Students who have fallen behind in understanding galaxies and the Milky Way
  • Students who struggle with learning disabilities or learning differences, including autism and ADHD
  • Students who prefer multiple ways of learning science (visual or auditory)
  • Students who have missed class time and need to catch up
  • Students who need an efficient way to learn about the Milky Way
  • Students who struggle to understand their teachers
  • Students who attend schools without extra science learning resources

How it works:

  • Find videos in our course that cover what you need to learn or review.
  • Press play and watch the video lesson.
  • Refer to the video transcripts to reinforce your learning.
  • Test your understanding of each lesson with short quizzes.
  • Verify you're ready by completing the Milky Way chapter exam.

Why it works:

  • Study Efficiently: Skip what you know, review what you don't.
  • Retain What You Learn: Engaging animations and real-life examples make topics easy to grasp.
  • Be Ready on Test Day: Use the Milky Way chapter exam to be prepared.
  • Get Extra Support: Ask our subject-matter experts any question about the Milky Way. They're here to help!
  • Study With Flexibility: Watch videos on any web-ready device.

Students will review:

This chapter helps students review the concepts in a Milky Way Galaxy unit of a standard Intro to Astronomy course. Topics covered include:

  • Formation of elliptical, irregular and spiral galaxies
  • Structure, shape and spiral arms of the Milky Way
  • Population I and II stars
  • Origin, location and movement of the solar system
  • Galactic mass
  • Dark matter

8 Lessons in Chapter 24: The Milky Way Galaxy: Help and Review
Test your knowledge with a 30-question chapter practice test
Population I and Population II Stars

1. Population I and Population II Stars

This lesson will explore the different populations of stars in our galaxy, including population I and II stars, as well as where you can find them and what metals are to an astronomer.

How Our Galaxy Was Discovered

2. How Our Galaxy Was Discovered

This lesson will outline for you the basics of how the galaxy you live in, the Milky Way Galaxy, was discovered over time. You'll also learn about RR Lyrae and Cepheid variable stars.

Density Wave Theory & Spiral Galaxies

3. Density Wave Theory & Spiral Galaxies

This lesson will teach you about the spiral arms of the galaxy: namely, the major theory that tries to explain their existence as well as why the spiral arms look so different in various kinds of spiral galaxies.

The Formation of the Milky Way Galaxy

4. The Formation of the Milky Way Galaxy

This lesson will explore two hypotheses as to how the Milky Way galaxy formed. These are the top-down and bottom-up hypotheses. We'll also go into what special connection you personally have to all of this.

The Structure of Our Galaxy

5. The Structure of Our Galaxy

If you ever looked up at the night sky far away from city lights, you would've seen a band of light across the night sky and lots of stars scattered around the rest of the sky. Why? The structure of our galaxy will explain exactly why.

The Mass of Our Galaxy

6. The Mass of Our Galaxy

This lessons explores the estimates and numbers surrounding the mass of the Milky Way Galaxy and how they relate to Keplerian motion, the galactic corona, and dark matter.

The Spiral Arms of the Milky Way Galaxy

7. The Spiral Arms of the Milky Way Galaxy

How do we know our galaxy has spiral arms? You can't really see them, but we can infer they're there thanks to radio waves and observations of other galaxies, which you will learn about in this lesson.

The Nucleus of a Galaxy

8. The Nucleus of a Galaxy

This lesson will explore our galaxy's nucleus. Namely, we will find out how we can peer inside using radio waves and infrared, and what that and X-rays tell us about the cool thing that's located inside of it.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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